diff --git a/src/settings.cpp b/src/settings.cpp
index 246420776d..59ece2a8e9 100644
--- a/src/settings.cpp
+++ b/src/settings.cpp
@@ -1392,6 +1392,7 @@ static bool ImprovedBreakdownsSettingChanged(int32 p1)
 static bool DayLengthChanged(int32 p1)
 {
 	SetScaledTickVariables();
+	MarkWholeScreenDirty();
 	return true;
 }